Back rest cushioning device for chairs



sept. 14, 1943, G. D. woon 2,329,673

,'BAGK REST CUSHIONING DEVICE FOR CHAIRS Filed June 20, 1941 i 22@ in j@ Y a i 2524351 Patented Sept. 14, 1943 CHA IRS

GlennD. Wood, Elkhart, Ind., assigner to Posture Research Corporation, Elkhart, Ind., a corporation of Indiana Application'iuneao,1941, serial No. ssassi solaims. (o1. 1554164),

1'" This invention relates toimprovements in back rest cushioning devices forchairs and it consists 'in the matters hereinafter describedand more `particularly pointed out in the appended claims.

VThejcushioning device with which vthe present Vinvention is more especially concerned, is of the kind illustrated anddescribed in' my prior Patent 2,018,825` of October 29, 1935,`and which device isthereinshown as disposed between the seat of a chair Yand a back rest, which'is mounted Vfor a forward and a backward movement with'jrespect to the seat. p One of the objects of the .present invention is to provide a device of this kind whereby'thetension ofthe cushioning element, embodied in the device, may be more easilyadjusted.

A further object of the invention is to provide a device of this kind having certain-of its parts swivelly connected together so that theyican'not become separated while making an adjustment of the cushioningelementjof the' device. A

Again, it is' an object' of the invention to'p'ro- Vide adevice ofthis kind wherein certain' threading operations, necess'aryin" thesame as heretofore' constructed, may be' eliminated 'so that 'the device is more simple" and less"y costly" to make and 'this without sacricingthe efiiciencyof the operation thereof. .A

The above mentioned objects'of the invention, as well as others, together with the: advantages thereof will more fully appear as the specication proceeds.-

In the drawing: 'f j Fig. 1 is a View in side elevation of the seat and the backrest of a chair offthe kind' mentioned,

with one of the improved cushioningdevicesy arranged therebetween toI cushion the back and forth swinging movement of' the backrest withl respect to the seat. I k

Fig. 2 is a longitudinal sectional vview through the improved cushioning device, on a somewhat venlarged scale; when the device is removedA from its position in the chair, j f

Fig. 3 is a transverse sectional View through the improved cushioning device, as takenon the the back rest may' lupholstered and'wliileutnis is preferablait is not essential.,`

The'backlrestjis 'disposed 'above the back of the pair of :supporting arms'j lf2; ,Whilej only oneof such arms appears in"l.?ig. v1, lit is of course tob'e` understoodtliatthere'istone of sucharms ateach side ofthe chair.L The lower end'of each' arm vl2 is pivotally connected as at I3"to Vt'hejseat and 'whereby the back rest is capable of'iab'ack'and AforthV swinging movement `with resp tA toft'ne seat. j -j To cushion `the"ba'ckward VVswinging `movement i of the backrest 'from itsnormal atlrest'V position .and'to return' it to thatjposition after 'a ,backward movement of the `bac krest,I'prfovide'a device 'I4 between each ,arm I2 andthe seat Il); Said', de-

orlinkandjbest appears in Fig. 2.,l l l Each device embodies a ,tubular vnjiemlmerjf'ji5 vice is in the nature of a yielding 'telescopicbace that isflattened-at Yone -end to `.form anfearfl5a line 3-3 of Fig. 2 and'on a scale'somewhatv en'- larged overV that of Fig; 2..

Fig. 4 is a perspective View of a certain spring housing element embodied in theimproved cushioning device and which will be vmore fully referred to later.

Referring now in detail to that embodiment of the invention illustratedinfth drawing, l0` indicates theQseat of an oiiicechair'and, Il indicatesv the back fest washer-zien, @been :and

Athrough which a bolt or screwl lfextends'to p ivlotally connect this endof they device as a whole tothe associated vback rest supporting arm" l2;l

In the other end of) the tubular member l '5, is located a tubular` spring `housing il' (s'eefiig'sj.` 2 and 4) and inthat end of vthe,loousing facing the ear I5a is a pair of longitudinally,extendin'gfdi- *ametrically opposite ,slots lfthat openfthrough said end of thehousingj The kother end of said vhousing reoeives'and isfweldedras at" v9 to "the body 20 of abushing -Zlthat has a head1@ .of a diameter approximating ythat ofi'thef tubular member I 5.v The head His/spaced fromthassociated end of'the'housingso' asjto provide an `annular groove` 23 (see Fig. 2') Vtherebetween and into which the end? portion1 `:llbforthe tubular member l5 is upset. The structure-"just mentioned provides* a swivelling connection y lbetweenv the tubular"member lj'andj the tubularv housing 11, sol that a relative turning movemeptispossible therebetween without aA relative'longitudinal movement orwseparation. Therbodyy 20 of the bushing'is provided with axial bolgportions y24 and 24arespectively of diffe'rentniameters and the meeting ends'of saidbore portion's'iorm an annular lstop shoulder 24h.v nThe head' ci' the bushing has ``radialv recesses' 'ZZaftherein `into which Aanyv simple Vdevieernay be inserted for turning the, vbushing) relatively 'to thetubular member l5.

Apart of a rod orl stem`2thassli'ding engagement inthe borep'ortiongfl,and afsleevfe; 512,5 is

xed to' said4 stem fory rodA at a point, v`thereonso as .to have 'a' sliding engagementrin ithebcre 'porthe inner end of the stern or rodexterdsbeyondf the inner end of the housing and the inner end of the stem or rod is threaded-as at 29rin-Fig.2;

An abutment member Bil-*has -a threaded' engagement on the part 29 of the stem or rod 2'5 and has a fairly snug t in thehousing I1.. .Said 'abutment member is in the form of a relatively thick washer and has radial projectionsl-that engageinthe slots |43. in `thehousing I'Ly Because of the engagement of saidproje'ctions in said slots, said abutment membercannotl -turn .with respect to y'the"housing"bui; y'it'A can move longitudinally .f-the stem and saidhousing; when said housing-is turned as will soon appear.. Thus a. sliding splined connection isafforded between .dated therewith.

'A resilientrneans in-the'fform-of 1an expanythev housing and the abutment memberfll assolsion spring '32 surroundsl a. part` o'the rod'fl and engages at its ends with rsaid abutment"3l and the body 20 ofthe bushingZl, If desired, a lock nut`33 may be proyidedonfthe threaded -end of said rod outwadlyf--the abutmentfthere- -ion'. Preferably thespIirig' isgm'adeof. rectangular cross sectional sto'clc'as shown. f

Assume that there is .af cushioning-device-vop eratively securedat-its"en',ds,y one t oeachlback rest supporting arm`l2 andl to theseatfl Il) jre- .spectively When the occupant'oflthe seat leans backagainst'the back rest,.a force-.islexerted, tending to swing"thebackrestfll .rearwardly against the action .of the springs .532-132. of.-both cushioning devices Ill-M. nIn this backward Imovement of theback re'st,thedelvices` I'dfM will tend to elongate,` therebyplacingethe springs 32;"32-under compression, untilthe sleevesl 25. of

both cushioning devices engage theireassociate'd bushing shoulders". 2lb WhichVof coursel'limitslthe 'backward movement-.of said backrest. when the occupant leansor movesqforwardlyonthe seat, theY pressure .against .thea backreste-is eased Vor released` and the springs32-32 expandand shorten'the devicesl to return-fthe fback. `rest -tov .beyond 'saidother. end of said-*tubular portion,

its normalpositionfwhen. thelfsleeves. 25fagain occupy the positionshownin Fig. 2.

By inserting the. endof .aesimple'implement suchas a nail,` in one'oflthe recesses- 22mm/the head V22 of each bushingsadbushings-maybe* 'turned 'with respecttoethetubular member 15.

AByfreasonlof the sliding. splined. connection=-between vthe housing'll ofM each ldeviceandjthe associated. abutment member, whenlthe bushing-.is turned `in' one ldirection, the abutment-.member '.30 will move toward rthe vassiiciated bus-hingeleso that the compression ofthe springf'32 therebetween is increased. When 'thefbush'ing is .turned in the other ydirection,-lthe fab'utmentfmember movesu away from the bushing so 'thatfthe .spring expands, reducing the compression ofilthespring. Thus, theaction of the springs 32 'of -both'ldevices |4-I4 associated `With thechair'nlay' be quickly and easily adjusted to suit the occupant.

The stein il O ' While ini describingthe"inventionfI have re- 'ferred in" 'detail' to' 'the' form, 'arrangement and construction of the parts employed, the same is to be considered only in the illustrative sense, and therefore I do not wish to be limited thereby except as may be specically set forth in the appended claims.

I claim as my invention: l. .iA-cushioning device' for usci-between the seat member-f -a chair and-fa 'back rest member mounted for a back and forth movement with refspect to said seat member, said device embodyingtlierein-.apart having means at one end :'fadaptd'to be operatively connected to one of sai-d members so Vas to be held against axial 'turnifngtherebyiand.having a tubular portion at -itstherienda tubular member disposed in said tubular portion, a bushingxed to one end of A"said-tubularmember and forming therewith an 4longitudinal separation, a 'stem `s`lidable..`throu'gh said bushing and having .a 4threaded vpartidisposd.- in the'other eridoffsaidftubularfmember and having. a second part extending outwardly -beyond said bushing and' having 'meansadapted to be-operatively connected to the. thenoisaid vhrst mentioned members to be yheld -again'staxial turning thereby, resilient means in saidltubular member and. surrounding a part of said-.stemand engaged at one '.endwi'th a`- part. of. said bushing, .andl an llabutm'entmember mounted .on said 'threaded part ofsaidstem' and engaged with. the

other end of saidresilient means, said' tubular Vmember and said abutment member-having-a sliding splined connection -so' that when' said'..bu'sh 'ing is turnedin onedirection. or 'the other, the

abutment 4memberlis caused lto move longitudinally on'the 'stem'.towardor awayfromisaid 'bushing' to compress said resilient means or vto permit the same toiexpand.Y

6.2."Acushi'oning device 'for use"between, 'the seat'member of ajchair anda` backrest member mounted fora back and forthv movement with respect to said seatmemb'er, saiddeviceembo'dying therein-a part .having means. at.. one.en`d

adaptedlto 'be operatively connectedltofoneeof .said tubulanportion, a busliing'xed to oneend of said tubular member andformingtherewith an assembly, a, part 'of which. is..disposedoutwardly said-tubular member' beingformed with' longitudinal v'slots in its other end,..meansprovfidinT a swivelled connection betweensad. o`ther..iend

ofls'aid tubular portion andsaid assemblyI part and whereby said tubular. membenandesaidsassembly part may turn relatively without longitudinal separation, a. stem slid'able 4.throughsaid bushing and having' a threaded part'disposed at least in part in said tubular member anda second part" 'extending outwardlyl from the -bushingand having means adaptedv to beoperatively connected to the other of saidlnrst mentioned members' te be held against .axial turning' ther'eby,. `resilient meansV in said tubular member and engagd'at ,one end with a part of said bushing, and anabut- "slots of' said 'tubular vmemberV and engaging. with "75' the otherendbi' said re'sl'lientmeans so that'wh'en said bushing is turned in one direction or the other, the abutment member is caused to move longitudinally on said threaded part of the stem toward and away from the bushing to compress said resilient means or to permit it to expand.

3. A cushioning device for use between the seat member of a chair and a back rest member mounted for a back and forth movement with respect to said seat member, said device embodying therein a part having means at one end adapted to be operatively connected to one ofsaid members so as to be held against axial turning thereby and having a tubular portion at its other'end, a tubular member disposed in said tubular portion, a bushing xed to one end of said tubular member and forming therewith an assembly, a part of which is disposed outwardly beyond the other end of said tubular portion, said tubular member and said bushing being constructed to coact in defining an annular groove in said assembly and into which an end part of said tubular l atively connected to the other of said rst men- I tioned members to be held against axial turning thereby, said stem part in said tubular member being threaded, resilient means in said tubular member and engaged at one end with a part of n said bushing, an abutmentmember mounted on J the threaded part of said stem and engaging the other end of said resilient means and having parts slidably engaged in said slots so that when said bushing is turned in one directionl or the other,

the abutment member is caused to move longitudinally on the stem toward or away from said bushing to compress said -resilient means or to permit the same to expand.k s y 4. A cushioning device for use between the seat member of a chair and a back rest member mounted for a back and forth movement with respect to said seat member, said device embodying therein a part having meansl at one end adapted to be operatively connected to one of said mem-v bers so as to be held against axial turning thereby and having a tubular portion at its other end, a tubular member disposed in said tubular portion, a bushing fixed tol one end ofl said tubular member and forming therewith an assembly, a part of which is disposed outwardly beyond said other end of said tubular portion, means providing a swivelled connection between said other outwardly beyond said bushing having means adapted to be operatively connected to the other of said rst mentioned members to be held against axial turning thereby, coacting means between said stem and bushing respectively for limiting the movement of the stem in one direction through said bushing, resilient means in said tubular member and surrounding a part of said stem and engaged at one end with a portion ofA said bushing, an abutment member mounted on the thread part of saidstem and engaged ,with

the other end of said resilient means, said tubular member and said abutment member having a sliding splined connection so that when said bushing is turned in one direction or the other,

the abutment member is'caused to movel longi-v tudinally of the stem toward or away from said bushing to compress said resilient means or to permit the same to expand.

5. A cushioning device for use between the seat member of a `chair and a back rest member mounted for a back and forth movement with respect to said seat member, said device embodying therein a part having means at one end adapted to be operatively connected to one of said members so as to be held against axial turning thereby and having a tubular portion at its other end, a tubular member disposed in said tubular portion, a bushing iixed to one end of said tubular member and forming therewith an assembly, a part of which is disposed outwardly beyond said other end of said tubular portion, means providing a swivelled connection between said other end of said tubular portionand said assembly part and whereby said tubular portion and said assembly may turn relatively withoutlongitudinal separation, saidbushing having a bore therein with a shoulder at one end thereof, a stem slidable through the bushing and having atheraded part in said tubular portion and having a part extending outwardly beyond the bushing and adapted to be operatively connected to the other of the first mentioned members to be held against axial turning thereby, means providing a shoulder on the stem and disposed in the bore in said bush-` ing and adapted for engagement with the shoulder at one end of said bore for limiting movement of the stem through the bushing in one direction, resilient means in said tubular member and surrounding a part of said stem and engaged at one end with a portion of said bushing, and

end of said tubular portion and said assembly an abutment member mounted on said threaded part of the stem and engaged with the other end of said resilient means, said tubular member and said abutment member having a sliding splined connection so that when said bushing is turned` in one direction or the other, the abutment member is caused to move longitudinally of the stem toward or away from the bushing to compress said resilient means or to permit the same to expand.

GLENN D. WOOD. 

